The present invention relates to a network relay apparatus for conducting data transfer, and in particular to a network relay apparatus which reduces power consumption.
In Internet service providers and basic networks of intra-enterprise networks, network relay apparatuses which transfer frames by using a plurality of network LSIs are becoming utilized. In such a network relay apparatus, all network LSIs have operated conventionally with a clock and an operation voltage which maximizes the performance regardless of whether the network traffic is large or small. Even if the data transfer quantity is small, therefore, the power consumption cannot be reduced. When the network traffic is small depending upon the time zone and time, wasteful power consumption is caused.
In JP-A-2003-87296, system clock frequency control is exercised by monitoring the connection state every line and monitoring the flow of the network traffic in order to reduce the power consumption in the network relay apparatus. In JP-A-2003-87296, movement to a low power consumption state is conducted in a line in the network relay apparatus when a connection state is not detected or when data communication is not generated over a long time period. Furthermore, system clock frequency control is exercised according to the flow of the network traffic.